Apparatus for grinding welding electrodes, in particular wolfram electrodes

ABSTRACT

The invention is a grinding apparatus for grinding tips of welding electrodes. An apparatus for grinding welding electrodes in accordance with the invention includes a drive motor for rotating a grinding disc and an electrode holder for fixing a welding electrode at an angle in relation to the grinding disc, the holder having a part which is displaceable vertically parallel to a plane of the grinding disc on a guide including first and second mutually displaced receivers for the electrode holder, the first receiver being positioned adjacent a scale provided on an outside of a housing which is used to set an angle at which a point of the electrode is to be ground with a radius of the scale being equal to a radius of the grinding disc and the second receiver fixing the electrode holder, which holds an electrode held therein having an end at which a point is to be ground by the grinding disc, parallel to the plane of the grinding disc with the point of the electrode engaging part of a periphery of the grinding disc with a vertical distance between the receivers being equal to a distance between the scale and the grinding disc.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for grinding weldingelectrodes, in particular tungsten electrodes.

2. Description of the Prior Art

Known grinding apparatuses for grinding welding electrodes work with arotating grinding disc, where the welding electrodes are pointed bypressing against a side surface of the grinding disc in a wanted angle.This grinding principle makes it complicated to vary the grinding angleor the point of the electrodes. Furthermore it is realized, that thisgrinding principle or grinding apparatus involve some unsolvedenvironmental problems in connection with the aggressive grinding dustresulting from the grinding of welding electrodes containing tungsten.

SUMMARY OF THE INVENTION

The invention has for its purpose to provide an improved apparatus forgrinding of welding electrodes, and which by means of simple provisionsmakes it easier to adjust the grinding angle; as the apparatus in apreferred embodiment may satisfy environmental problems in connectionwith for instance grinding of tungsten electrodes.

The apparatus according to the invention is distinctive in that afixingcomprising an apparatus part arranged to be displaceable parallel to theplane of the grinding disc on a fixed guiding extending vertically,which apparatus part comprises two mutually displaced insertion openingsor insertion positions for an electrode holder, namely a first insertionopening or position in front of an arched angle scale provided on theexternal side of a housing the radius of the arched angle scale is equalto that of the grinding disc) and a second insertion opening or positionsituated and adapted to fix the electrode parallel to the plane of thegrinding disc with the point engaging the upper part of the periphery ofthe grinding disc (the vertical distance) between the insertion openingsis equal to that between the arched angle scale and the grinding disc).By means of simple provisions a grinding apparatus is hereby obtained,which makes it easier to adjust the wanted grinding angle.

Appropriately the apparatus according to the invention is furthermoresuch provided, that the grinding disc is arranged in a grinding housingpreferably built together with a drive motor, the housing being closedwith a preferably transparent wall part, and being adapted to be filledwith a grinding fluid, preferably water. In a simple manner the theenvironmental problems with aggressive grinding dust are hereby met, bywhich manner for an effective collecting of the grinding dust containingtungsten and having a considerable reusable value, furthermore isobtained.

In order to minimize the spraying from the rotating grinding disc, ofwhich the lowermost part is surrounded by the grinding water, theapparatus may advantageously be such provided, that the grinding housingdownwards has larger width, and that the grinding housing in front ofthe grinding disc comprises an(from the bottom) upright partition wall,which lowermost is provided with one or more flow through openings. Dueto the rotation of the grinding disc the main part of the grinding fluidis forced out through said flow through openings, so that the fluidlevel under the grinding disc is minimized.

Also to keep the grinding fluid effectively inside, the apparatusaccording to the invention may be such provided, that the displaceableapparatus part preferably is waterproof connected with the grindinghousing, as there in a side wall part of the grinding housing in frontof the active insertion opening or the active insertion position for theelectrode holder a flexible, oblong lip tighting is arranged, throughwhich the outermost end of the electrode holder may be inserted.

BRIEF DESCRIPTION OF THE DRAWING

The invention is explained in more detail in the following withreference to the drawing, in which:

FIG. 1 shows a view—partly in section—of a preferred embodiment for agrinding apparatus according to the invention—seen from the front, and

FIG. 2 shows a side sectional view of the grinding apparatus shown inFIG. 1.

The shown grinding apparatus 2 is provided as a transportable unit withan electric motor 4, a closed grinding housing 6 with a rotating,relatively thin grinding disc 8. The grinding housing 6 is builttogether with an upper handle 10, which from a mainly triangular gableplate 12 projects over the electric motor 4, that is that the balance ofthe grinding apparatus 2 is optimum.

As most clearly shown in FIG. 2 the grinding house 6 has a mainlytriangular cross section with most width below. The grinding housing 6is closed outwardly by means of a clear acrylic plate 14, which makes itpossible to watch the fluid level, as water is filled in the grindinghousing 6, so that the grinding disc is kept wet during the grindingprocess, and so that the grinding dust is collected in the grindingfluid. In the bottom of the grinding housing 6 a partition wall 16 withlower flow through openings 18 is placed in front of the grinding disc8. The partition wall 16 has the primary function—during the rotation ofthe grinding disc —to keep most of the grinding fluid away from thegrinding disc 8 to limit the spraying from the rotating grinding disc 8.When the grinding disc 8 stands still the fluid level of course is equalon both sides of the partition wall 16; but when the grinding disc 8rotates, most of the grinding fluid is forced to the front of thepartition wall 16, that is that the fling off of the grinding fluid isminimized.

During the grinding work the welding electrode to be grinded is fixed ina n electrode holder 20, which for the fixing of the welding electrodeis provided with holding device using the same holding principle as thatof a drilling cartridge or of a press pencil. The front end of theelectrode holder 20 is inserted in the grinding housing 6 throughtightening device 22 in a side wall part 2 1, so that the electrodepoint itself may be pressed tangentially against the periphery of thegrinding disc, that is that the tightening device 22 in the height isstretching over the whole adjustment area of the electrode holder.

In other words the electrode point according to the invention is grindedby pressing against the periphery of the grinding disc 8, and theadjustment of a wanted point angle is obtained by the fact that theengaging area between the electrode, when it is placed in the firstinsertion opening 26, and the grinding disc 8, is moved along the upperpart of the periphery of the angle scale 28 to the wanted angleposition. This is obtained by displacing the displaceable apparatus partin a fixed guiding in a direction parallel with the plane of thegrinding disc, and by situating and adapting the second insertionopening 30, such that the electrode is fixed parallel with the plane ofthe grinding disc 8 for engaging the electrode point against the upperpart of the periphery of the grinding disc 8.

The grinding apparatus 2 is at the right handside of FIG. Cl providedwith a height displaceable sliding bracket 24, which cf. FIG. 2 has twomutual fixed insertion positions or openings for the electrode holder20, namely an upper, first insertion opening 26 for insertion of theelectrode holder 20 in order to adjust the point angle of the weldingelectrode in relation to the angle scale 28 on the front of the grindinghousing 6, and a lowermost, second insertion opening 30 positioned onlevel with the wanted angle position of the periphery of the grindingdisc, as the sliding bracket 24 may be adjusted in relation to the fixedguiding 32 by means of a finger screw 34.

What is claimed is:
 1. An apparatus for grinding welding electrodescomprising: a drive motor for rotating a grinding disc and an electrodeholder for fixing a welding electrode at an angle in relation to thegrinding disc, the holder having a part which is displaceable verticallyparallel to a plane of the grinding disc on a guide including first andsecond mutually displaced receivers for the electrode holder, the firstreceiver being positioned adjacent a scale provided on an outside of agrinding housing which is used to set an angle at which an end of theelectrode is to be ground into a point with a radius of the scale beingequal to a radius of the grinding disc and the second receiver fixingthe electrode holder which holds an electrode held therein having theend at which the point is to be ground by the grinding disc parallel tothe plane of the grinding disc with the point of the electrode engagingpart of a periphery of the grinding disc with a vertical distancebetween the receivers being equal to a distance between the scale andthe grinding disc.
 2. An apparatus in accordance with claim 1, wherein:the grinding disc is positioned in the grinding housing, the grindinghousing being closed with a wall and containing a grinding fluid duringgrinding.
 3. An apparatus in accordance with claim 2 wherein: a shaft ofthe drive motor is connected to the grinding disc and extends fromoutside the grinding housing to the grinding disc.
 4. An apparatus inaccordance with claim 3 wherein: the grinding housing comprises atransparent wall which makes visible the grinding disc from outside thegrinding housing.
 5. An apparatus in accordance with claim 4 wherein:the grinding fluid which is contained in the grinding housing is water.6. An apparatus in accordance with claim 5 wherein: the grinding housingat a base thereof is wider than at a top of the grinding housing andcomprises in front of the grinding disc an upright partition wall whichat a lowermost part is provided with at least one flow through opening.7. An apparatus in accordance with claim 6, wherein: the holder isconnected to the grinding housing, a side wall part of the grindinghousing is disposed in front of the second receiver of the electrodeholder, and an outermost end of the electrode is insertable through atightening device.
 8. An apparatus in accordance with claim 5, wherein:the holder is connected to the grinding housing, a side wall part of thegrinding housing is disposed in front of the second receiver of theelectrode holder, and an outermost end of the electrode is insertablethrough a tightening device.
 9. An apparatus in accordance with claim 4wherein: the grinding housing at a base thereof is wider than at a topof the grinding housing and comprises in front of the grinding disc anupright partition wall which at a lowermost part is provided with atleast one flow through opening.
 10. An apparatus in accordance withclaim 9, wherein: the holder is connected to the grinding housing, aside wall part of the grinding housing is disposed in front of thesecond receiver of the electrode holder, and an outermost end of theelectrode is insertable through a tightening device.
 11. An apparatus inaccordance with claim 4, wherein: the holder is connected to thegrinding housing, a side wall part of the grinding housing is disposedin front of the second receiver of the electrode holder, and anoutermost end of the electrode is insertable through a tighteningdevice.
 12. An apparatus in accordance with claim 3 wherein: thegrinding housing at a base thereof is wider than at a top of thegrinding housing and comprises in front of the grinding disc an uprightpartition wall which at a lowermost part is provided with at least oneflow through opening.
 13. An apparatus in accordance with claim 12,wherein: the holder is connected to the grinding housing, a side wallpart of the grinding housing is disposed in front of the second receiverof the electrode holder, and an outermost end of the electrode isinsertable through a tightening device.
 14. An apparatus in accordancewith claim 3, wherein: the holder is connected to the grinding housing,a side wall part of the grinding housing is disposed in front of thesecond receiver of the electrode holder, and an outermost end of theelectrode is insertable through a tightening device.
 15. An apparatus inaccordance with claim 2 wherein: the grinding housing at a base thereofis wider than at a top of the grinding housing and comprises in front ofthe grinding disc an upright partition wall which at a lowermost part isprovided with at least one flow through opening.
 16. An apparatus inaccordance with claim 15, wherein: the holder is connected to thegrinding housing, a side wall part of the grinding housing is disposedin front of the second receiver of the electrode holder, and anoutermost end of the electrode is insertable through a tighteningdevice.
 17. An apparatus in accordance with claim 2, wherein: the holderis connected to the grinding housing, a side wall part of the grindinghousing is disposed in front of the second receiver of the electrodeholder, and an outermost end of the electrode is insertable through atightening device.
 18. An apparatus in accordance with claim 1 wherein:the grinding housing at a base thereof is wider than at a top of thegrinding housing and comprises in front of the grinding disc an uprightpartition wall which at a lowermost part is provided with at least oneflow through opening.
 19. An apparatus in accordance with claim 18,wherein: the holder is connected to the grinding housing, a side wallpart of the grinding housing is disposed in front of the second receiverof the electrode holder, and an outermost end of the electrode isinsertable through a tightening device.
 20. An apparatus in accordancewith claim 1, wherein: the holder is connected with the grinding house,a side wall part of the grinding housing is disposed in front of thesecond receiver of the electrode holder, and an outermost end of theelectrode is insertable through a flexible oblong lip tightening.